The Moon slides across the constellation Taurus on the nights of October 4-5, passing close to the bull's bright orange "eye," Aldebaran. The brilliant planet Jupiter is also passing through Taurus, enhancing the display. The blue triangle at the center of this illustration shows the bull's face, which is outlined by Aldebaran and the Hyades star cluster, which is much closer than the tiny Pleiades cluster at top. This view is around 11 p.m., with the grouping scooting across the southern sky later on.

A bright, skinny triangle climbs high across the sky late tonight — the Moon, the planet Jupiter, and the star Aldebaran, the “eye” of Taurus, the bull. They’re in good view in the east by around 10 or 11 o’clock, with Aldebaran close to the lower right of the Moon and brilliant Jupiter farther to the lower left.

Jupiter is the largest planet in the solar system, and it outweighs all the other planets and moons combined. Thanks to that great mass, it shepherds an entourage of more than 60 known moons, plus several thin, dark rings.

Jupiter’s gravitational influence doesn’t end there, though — it extends throughout the solar system.

For one thing, Jupiter’s gravity traps two clumps of asteroids. They share Jupiter’s orbit around the Sun, but they’re well ahead of and behind the giant planet.

For another, Jupiter can deflect comets onto new paths. This role is important for Earth — Jupiter prevents many comets from reaching the inner solar system, where they could threaten our planet.

And in the distant past, Jupiter affected the layout and even the population of the solar system. Gravitational interactions with the other three giant planets pushed all of the giants into their current orbits. And Jupiter kept a ring of material that’s between Jupiter and Mars from coalescing to form a planet. Today, the remnants of that failed planet form the asteroid belt — a band of rubble courtesy of giant Jupiter.

Script by Damond Benningfield, Copyright 2012

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